Labor cost, construction drawing change cost is calculated by multiplying the original contract unit price by the increased workload. Designers, should we charge design fees? Designers are divided into two categories: "experienced designers": those who have worked for more than 3 years, have profound opinions on design and have relatively standardized design drawings. This kind of designer will definitely charge a design fee. Designer who just graduated: Less than 3 years' experience. This kind of designer is inexperienced, so it's good to have a client looking for him to design. How dare you charge the design fee? Some companies and designers use such designers under the banner of free design. Due to lack of experience, it is easy to cause many unrealistic design schemes of the project.